neil_P_smith

i am having problems with my carb. it will idle but it will not throtle up. it studders and then backfires through the carb. how do i set my carb up for the canaden vacume. i got the vacumes for the choke to work good and i think that i have the vacume advance working. only the outer vacume line dose any thing. what other vacumes do i need. the head dosent have egr so what is stoping it from reving out.
i have no clue and have tryed many diferent things what could this be. please help Neil

Bigblock

could also be major timing chain stretch.

Bigblock

whered my other post go?Anyway your timing is too slow.

neil_P_smith

Ok it is a new rebuild. And the whole lower end is new. I used a timing light and the timing is set at 8 degrees tdc with vacuum hooked up. The strange thing is that I had to move the rotor advanced one tooth to get it there. The outside (farthest to front) vacuum on the distributor is the only one that dose any thing?? This is on a 81-84 22r bored 30 over and a 20r head with a 22r carb. If I adjusted it by sound and advanced it would that do any damage to the motor?? Thanks a lot for any help I can get Neil

kyle_22r

here's a link to the canadian vacuum diagram - https://www.yotatech.com/attachment....achmentid=4736

the only things i have blocked off on that are the charcoal canister(i don't have one on my truck anyway, previous owner probably took it off) and the thermo switch/HAI(i have an open element air cleaner, kind of pointless to hook these up). runs GREAT, especially since i had the carb rebuilt, but i'm gonna have to take it off and have them set the float level, since they put it so low it sputters out under any load

what kind of shape is your carb in? might be overdue for a rebuild if hooking everything up right doesn't work. if you or somebody else messed with the idle mix screw(it's at the bottom of the carb, you have to drill out a plug to get to it), turn it all the way in then back it out to its baseline of 2.5 turns out. generally you don't want to mess with that.

neil_P_smith

kyle thanks, i got it figered out today. i gess i just needed some time off of it. today i read the book again and some how i had mised the part about taking the vacume lines off to set the timming before. oops i have a clymer supper and it gives grate info on the vacume. i reabuilt the carb with the corect rebuild kit about 6 months ago. so the carb is good. i dont have the thermo or that other one hoked up eather. but now that i have set the timming right it runs sweet. i will probly adjust the mixture screw because it might not be the same with it bored 30 over and the 20r head on there. thanks a lot every one it was starting to make me mad and i spent the weekend away from it. Neil

kyle_22r

generally the mixture screw adjustment is only needed if your engine is so modified that it needs a richer mix at idle. there's a good reason that it's plugged! don't think a 20R head would affect it too much since your displacement stays the same, it's just capable of revving higher.